Package com.esri.arcgisruntime.tasks.networkanalysis

Class ServiceAreaTask

  • All Implemented Interfaces:
    ApiKeyResource, RemoteResource, Loadable
    public final class ServiceAreaTask
extends Object
implements Loadable, RemoteResource, ApiKeyResource
    A task to compute areas that can be serviced (reached) from a given location using an ArcGIS Network Analyst service.

    A service area is a region that encompasses all accessible streets, that is, streets that lie within a specified impedance around a given facility. For instance, a 10-minute service area includes all the streets that can be reached within 10 minutes from that facility.

    To solve for service areas:

    1. Pass in Url of service to constructor ServiceAreaTask(String).
    2. Use the createDefaultParametersAsync() method to create a set of ServiceAreaParameters with default values.
    3. Make any necessary changes to parameters, for instance changing impedance value used in calculation. ServiceAreaTaskInfo stores all settings that can be changed in parameters.
    4. Set ServiceAreaFacilitys to parameters ServiceAreaParameters.setFacilities(Iterable). Service areas will be generated around these facilities. At least one facility must be added, otherwise an exception is thrown.
    5. Solve the ServiceAreaTask by calling solveServiceAreaAsync(ServiceAreaParameters), which returns a ListenableFuture for tracking when the operation is done.
    6. Get the ServiceAreaResult from the listener once the calculation is complete.
    7. Get service areas from result using ServiceAreaResult.getResultPolygons(int) or ServiceAreaResult.getResultPolylines(int). Polygons display an area around a facility that can be serviced within the impedance that was set. Polylines display all streets that can be serviced within that same area.

    Displaying ServiceAreaPolygons using a ServiceAreaTask from an URL: 

     // create service area task from url
 final String SanFranciscoRegion = "http://qadev000238.esri.com/server/rest/services/NA/SanFran_WithTM/NAServer/Service_Area_Defaults";
 serviceAreaTask = new ServiceAreaTask(SanFranciscoRegion);
 serviceAreaTask.loadAsync();

 ListenableFuture<ServiceAreaParameters> parameters = serviceAreaTask.createDefaultParametersAsync();
 parameters.addDoneListener(() -> {
   try {
     serviceAreaParameters = parameters.get();
   } catch (ExecutionException | InterruptedException e) {
     e.printStackTrace();
   }
 });

 serviceAreaParameters.setFacilities(serviceAreaFacilities);
 // find service areas around facility using parameters that were set
 ListenableFuture<ServiceAreaResult> result = serviceAreaTask.solveServiceAreaAsync(serviceAreaParameters);
 result.addDoneListener(() -> {
   try {
      // display all service areas that were found to mapview
      List<Graphic> graphics = serviceAreasOverlay.getGraphics();
      ServiceAreaResult serviceAreaResult = result.get();
      for (int i = 0; i < serviceAreaFacilities.size(); i++) {
        List<ServiceAreaPolygon> polygons = serviceAreaResult.getResultPolygons(i);
        // could be more than one service area
        for (int j = 0; j < polygons.size(); j++) {
          graphics.add(new Graphic(polygons.get(j).getGeometry(), fillSymbols.get(j % 2)));
        }
      }
   } catch (ExecutionException | InterruptedException e) {
     e.printStackTrace();
   }
 });
    Since:
    100.1.0
    See Also:
    ServiceAreaParameters, ServiceAreaResult, ServiceAreaTaskInfo

    • Constructor Detail

      • ServiceAreaTask

        public ServiceAreaTask​(String url)
        Creates a ServiceAreaTask with the given URL to a service area service. The service may be hosted in the cloud on ArcGIS Online or on-premises with ArcGIS for Server.
        Parameters:
        url - online service for service area
        Throws:
        IllegalArgumentException - if url is null or empty
        Since:
        100.1.0

      • ServiceAreaTask

        public ServiceAreaTask​(TransportationNetworkDataset dataset)
        Creates a service area task with a transportation network dataset.
        Parameters:
        dataset - a transportation network dataset
        Throws:
        IllegalArgumentException - if dataset or resources is null
        Since:
        100.3.0

      • ServiceAreaTask

        public ServiceAreaTask​(String geodatabasePath,
                       String networkName)
        Creates a service area task with a path to a geodatabase.
        Parameters:
        geodatabasePath - an absolute path to a geodatabase
        networkName - a network name
        Throws:
        IllegalArgumentException - if geodatabasePath is null or empty
        IllegalArgumentException - if networkName is null or empty
        Since:
        100.3.0

    • Method Detail

      • getServiceAreaTaskInfo

        public ServiceAreaTaskInfo getServiceAreaTaskInfo()
        Gets the metadata (default and possible values of properties such as travel modes, supported languages, etc.) about the network service used by this task. Use this information to help set the service area parameters that are used to create service areas.
        Returns:
        metadata about the network service
        Since:
        100.1.0
        See Also:
        ServiceAreaParameters, ServiceAreaTaskInfo, createDefaultParametersAsync()

      • createDefaultParametersAsync

        public ListenableFuture<ServiceAreaParameters> createDefaultParametersAsync()
        Executes an asynchronous operation to create a set of default parameters for creating service areas.
        Returns:
        a ListenableFuture for tracking when the operation is done and getting the result; also allows cancellation. Calling get() on the returned future may throw an ExecutionException if the operation fails.
        Since:
        100.1.0
        See Also:
        getServiceAreaTaskInfo()

      • getTransportationNetworkDataset

        public TransportationNetworkDataset getTransportationNetworkDataset()
        Gets the transportation network dataset.
        Returns:
        the transportation network dataset
        Since:
        100.3.0

      • getLoadStatus

        public LoadStatus getLoadStatus()
        Description copied from interface: Loadable
        Returns the LoadStatus of the loadable resource.
        Specified by:
        getLoadStatus in interface Loadable
        Returns:
        the LoadStatus of the loadable resource

      • loadAsync

        public void loadAsync()
        Description copied from interface: Loadable
        Loads the metadata of the loadable resource asynchronously.

        The load status changes from LoadStatus.NOT_LOADED to LoadStatus.LOADING. A listener can be added via Loadable.addDoneLoadingListener(java.lang.Runnable) that is invoked upon completion of the asynchronous load operation.

        If the load operation completes successfully, the load status will be LoadStatus.LOADED, which means the resource has loaded its metadata.

        If the load operation failed, the load status will be LoadStatus.FAILED_TO_LOAD and the error can be retrieved by calling Loadable.getLoadError().

        This method can be called concurrently and repeatedly, but only one attempt is ever made to perform the load operation. If a load operation is already in progress (LoadStatus.LOADING state) when loadAsync is called, it simply piggy-backs on the outstanding operation and the done loading listener added to the loadable resource is enqueued to be invoked when that operation completes. If the operation has already completed (LoadStatus.LOADED or LoadStatus.FAILED_TO_LOAD state) when loadAsync is called, the done loading listener is immediately invoked when added to the loadable resource.

        If a loadable resource has failed to load, calling loadAsync on it subsequently will not change its state. The done loading listener will be invoked immediately when added to the loadable resource. In order to retry loading the resource, Loadable.retryLoadAsync() needs to be used.

        A load operation that is in progress (LoadStatus.LOADING state) can be cancelled by calling Loadable.cancelLoad().

        Specified by:
        loadAsync in interface Loadable

      • retryLoadAsync

        public void retryLoadAsync()
        Description copied from interface: Loadable
        Loads or retries loading metadata for the object asynchronously.

        Will retry loading the metadata if the object's load status is LoadStatus.FAILED_TO_LOAD. Will load the object if it is not loaded. Will not retry to load the object if the object is loaded.

        For more details on the load process see Loadable.loadAsync().

        Specified by:
        retryLoadAsync in interface Loadable

      • cancelLoad

        public void cancelLoad()
        Description copied from interface: Loadable
        Cancels loading metadata for the object.

        Cancels loading the metadata if the object is loading, and always invokes the done loading listener.

        A load operation that is in progress (LoadStatus.LOADING state) can be cancelled by calling this method and the resource will transition from LoadStatus.LOADING to LoadStatus.FAILED_TO_LOAD state. If the load operation was successfully cancelled, a CancellationException will be returned from Loadable.getLoadError().

        Cancellation should be used carefully because all enqueued done loading listeners for that resource instance will get invoked with an error stating that the operation was cancelled. Thus, one component in the application can cancel the load operation initiated by other components.

        This method does nothing if the resource is not in LoadStatus.LOADING state.

        Specified by:
        cancelLoad in interface Loadable

      • addDoneLoadingListener

        public void addDoneLoadingListener​(Runnable listener)
        Description copied from interface: Loadable
        Adds a listener to the loadable resource that is invoked when loading has completed.

        The listener may be added at any point, whether the loadable resource has already completed loading or not.

        • For resources that are not loaded when the listener is added (LoadStatus is NOT_LOADED or LOADING): When the resource completes loading, the listener will be invoked on the UI thread if it is added from the UI thread, otherwise it is not guaranteed on which thread the listener is invoked.
        • For resources that are already loaded when the listener is added (LoadStatus is LOADED or FAILED_TO_LOAD): The listener will be called immediately, on the current thread.

        Alternatively, to be notified when there is any change in the load status, use the Loadable.addLoadStatusChangedListener(LoadStatusChangedListener) method instead.

        Specified by:
        addDoneLoadingListener in interface Loadable
        Parameters:
        listener - a Runnable that is invoked upon completion of the load operation

      • removeDoneLoadingListener

        public boolean removeDoneLoadingListener​(Runnable listener)
        Description copied from interface: Loadable
        Removes a done loading listener from the loadable resource.
        Specified by:
        removeDoneLoadingListener in interface Loadable
        Parameters:
        listener - the listener to be removed
        Returns:
        true if the listener was removed, otherwise false

      • addLoadStatusChangedListener

        public void addLoadStatusChangedListener​(LoadStatusChangedListener listener)
        Description copied from interface: Loadable
        Adds a LoadStatusChangedListener to the loadable resource that is invoked whenever the load status changes.

        Adding this listener on the UI thread will cause it to be invoked on the UI thread, otherwise it is not guaranteed on which thread the listener is invoked.

        The listener will not be called if added to a loadable resource that has already completed loading. To be notified when a loadable resource has completed loading, including if the resource is already loaded when the listener is added, use the Loadable.addDoneLoadingListener(Runnable) method.

        Specified by:
        addLoadStatusChangedListener in interface Loadable
        Parameters:
        listener - the LoadStatusChangedListener to be added

      • removeLoadStatusChangedListener

        public boolean removeLoadStatusChangedListener​(LoadStatusChangedListener listener)
        Description copied from interface: Loadable
        Removes a LoadStatusChangedListener from the loadable resource.
        Specified by:
        removeLoadStatusChangedListener in interface Loadable
        Parameters:
        listener - the LoadStatusChangedListener to be removed
        Returns:
        true if the listener was removed, otherwise false

      • getCredential

        public Credential getCredential()
        Description copied from interface: RemoteResource
        Gets the Credential that is set on the network-enabled resource.

        Only applicable if the resource is secured.

        Specified by:
        getCredential in interface RemoteResource
        Returns:
        the Credential, or null if there is none

      • setCredential

        public void setCredential​(Credential credential)
        Description copied from interface: RemoteResource
        Sets a Credential to be used by the network-enabled resource in the event of an authentication challenge. The default credential is null.

        Only applicable if the resource is secured.

        Specified by:
        setCredential in interface RemoteResource
        Parameters:
        credential - the Credential to be used for authentication

      • getUri

        public String getUri()
        Description copied from interface: RemoteResource
        Gets the URI of this RemoteResource. Typically this is the URI used to instantiate the object.
        Specified by:
        getUri in interface RemoteResource
        Returns:
        the URI of this RemoteResource